William a



(No Model.)

BARK MILL.

. Patented Dec. 22, 1885.

FIG 2 N. PETERS, PholoLilhngnpher. Wnxhinglon. D C.

UNITED STATES PATENT FFrcn.

WILLIAM A. WOODS, OF SANTA CRUZ, CALIFORNIA, ASSIGNOR TO JOHN C.HAGERTY, OF SAME PLACE.

BARK-MILL.

E PEC1PICATION forming part of Letters Patent No.332,854, dated December22, 1885.

Application filed April 20, 1885. Serial No. 162,848. (No model.)

To all whom it may concern.-

Be it known that I, WILLIAM A. WooDs, of Santa Oruz,Santa Cruz county,State of California, have invented an Improvement in Bark- Mills; and Ihereby declare the following to be a full, clear, and exact descriptionof the same.

My invention relates to an apparatus for cutting or reducing bark tofine particles for tanners use.

The machine consists of a drum rotating within an outer casing andhaving hollow cylindrical chambers with closed ends formed at intervalsaround its periphery, so that they open outwardly through the periphery.These chambers have curved knives or cutters fitted in them so thattheir edges project just beyond the periphery of the drum, and the barkbeing fed into an apron or chute in the case, which delivers it so thatit rests against the periphery of the drum, these cutters will shear itoff, so that it is discharged through the opening in the lower part ofthe case.

Referring to the accompanying drawings for a more complete explanationof my invention, Figure 1 is asection taken through the casing and drumtransversely to the axis or shaft. Fig. 2 is a vertical section of thecasing, showing a face or side view of the drum.

A is the exterior casing, having at one side an inclined chute or apron,B, into which the bark is placed so that its lower end may rest againstthe periphery of the drum 0 at a considerable angle with its face. Thelower end of this apron is hinged or pivoted as shown at D, and aslotted guide, E, is attached to the side of the apron above thepivot-point, so that the apron may be raised or lowered, and thus changethe rate at which the bark is delivered to the cutters. A slotted rackand screw, F, retains the apron at any desired point or angle. Thecylinder Chas chambers or semicircular depressions G formed in itsperiphery, these depressions forming considerably less than a completecylinder and opening through the rim or periphery of the drum 0, asshown at H. The ends of the chambers are .closed. \Vithin each of thesechambers is fixed a knife or cutter, I, having the same general curve asthe interior of the chambers,

the knife being secured by a set or holding screw, J, which passesthrough the slot K, formed in the rear portion of the cutter. This slotallows the edge of the cutter to be advanced as fast as it is worn awayby use and sharpening until it is necessary to replace it.

The operation of my machine is as follows:

The bark being placed in the apron or chute B after the latter has beenadjusted to the desired angle with reference to the cutters, the drum 0,with its cutters fitting into the depressions on its face,asdescribed,will be caused to rotate rapidly, and the cutters will act toshear the end of the bark off in fine shavings or particles, which willbe delivered into the open mouths of the chambers G, and the centrifugalforce of the rotating drum will be sufficient to discharge it as soon asthe chambers arrive opposite the opening in the lower part of the casewhere the bark will have a free discharge. By this construction I avoidthe necessity of passing the bark into the interior of the drum, and theshaft and all the interior portions are thus kept entirely clear of dustand dirt. The cylindrical chambers are formed transversely just withinthe periphery or rim and extend as far across as may be desired. Iprefer to make them to extend only apart of the way across the face, andto alternate in position so that the cutters act successively, as willbe seen in Fig. 2. This enables me to use a drum with a wide face, sincethe knives do not extend entirely across, and it will do a larger amountof work and will run more steadily on account of this construction.

Having thus described my invention,what I claimas new, and desire tosecure by Letters Patent, is-

1. In abark-machine,arotating drum having chambers formed; parallel withits face and with closed ends and cutters fitted to project beyond theedges of the chambers, in combination with an inclosing casing, and anapron by which the bark will be held in contact with the periphery ofthe drum as it rotates, substantially as hereinidescribed.

2. In a barkmill, a cylindrical rotating drum havinglongitudinal-cylindrical chambers with closed ends, and cutters in saidopenings, in combination with an exterior casing bers, with theircutting edges projecting having a feed apron or chute at one side, andthrough the openings, an inolosing-case, and means for adjusting andchanging the angle of an adjustable feed chute or apron, substanthe saidchute, substantially as herein detially as herein described. 15 5scribed. In witness whereof I have hereunto set my 3. In a bark-mill, arotating cylindrical hand. drum having cylindrical chambers with closedWILLIAM A. WOODS. ends formed within the drum parallel with \Vitnesses:its face, and openings through the face into H. 0. LEE, 10 the chambers,in combination with cutters or S. H. NOURSE.

knives curved to fit the interior of the cham-

